As loose as my arm was, it wouldn't rotate around the shaft. We can all acknowledge that from the universal problems encountered with the arm that it is a flawed design. Further compounded by the surrounding design flaw that requires 3 hours and $100 of gaskets, seals and replacement fluids to remove and replace the arm from the primary side. You can limp along, or improve and forget.
The primary case is too close to the end of the shifter shaft to allow the lever to slide out on the shaft far enough to get it off. I don't know how you could possibly pry the arm open far enough to fall off the shaft while it is installed. I suppose you could try it on an arm held in vise first and see how it works out, then try it for real in the confines behind your primary. The whole point of the Dremel cutting is to make it easy.
I've done the tranny-side alternative when I changed the shifter springs and shaft: removed the exhaust, removed the right tranny cover and the top cover. Carefully tapped out the carrier plate with the two shafts in it, then pulled out the gears in sequence until I got to the shifter shaft. Loosen the shifter arm. Somehow deal with the lock ring on the end of the shifter shaft behind the lever and pull it out, shifter lever drops to the floor. Reverse to reassemble.
vs an hour with a dremel tool......and a technical/design improvement. PM me for pictures.